This project examines the role of biased construal and evaluation processes in creating and perpetuating social distrust and conflict. Three parallel lines of experimental research are proposed. A first line of investigation examines partisans' perceptions of bias and objectivity in media coverage of political and social controversies. These studies will focus, in particular, on the conditions that produce a "hostile media effect" --i.e., the tendency of partisans to view even impartial and even-handed media coverage as hostile to, and biased against, their own position or candidate. A second line of research investigates parallel biases in the perceptions and reactions of disputants to third parties placed in the role of mediator for personal or social disputes. A third set of studies examines related biases in our perceptions of adversaries and our evaluations of any compromises or concessions they offer towards a solution of the dispute. These investigations will pay special attention to the causes and consequences of "reactive devaluation"--i.e., the tendency for partisans to attach less value to proposals and overtures simply because they have been offered by an adversary. In each of these cases, the proposed studies will involved three stages. Initial studies in each section will explore the rage of the problem, i.e., the magnitude and range of applicability of the hypothesized phenomenon. Then, a second set of studies will attempt to examine, more deliberately and more directly, a number of processes and mechanisms hypothesized to underlie the phenomenon. Finally, the last studies in each section will investigate the effectiveness of various potential remedies, derived from our theoretical analysis, in overcoming or forestalling the relevant effects. These studies will speak to classic theoretical questions concerning the interplay of cognitive, perceptual, and motivational processes that may lead to distortions and biases in human judgment and decision-making. They should also have important practical implications for our understanding and amelioration of the spirals of hostility and distrust that produce syndromes of escalating violence in personal and social relationships and for the development of procedures to facilitate successful mediation efforts and effective face-to-face negotiations.